The invention relates to a system constituted by electronic modules attached to each other, thus forming a stack that can comprise functionally different modules of all kinds electrically interconnected for transmitting signals between them and to the exterior, the said stack being fixed, for example, to a printed circuit card, a so-called master card, each module comprising an electric circuit constituted by components wired on a flat rectangular support and provided with contact regions along at least one of its sides and arranged in a flat insulation housing provided with means for holding in place both the circuit and a plurality of electric conductors independent of the circuit, an electric conductor each time corresponding to a region of the support and being pressed against it, the said housings all being mechanically identical to each other and being provided with means for securing them to each other. Such modules are used in an electronic system when the systems have to be readily adapted so that they can satisfy specific needs of the user, have to provide the possibility of being increased according to the variable needs of the user and have to provide the possibility of being readily modified. These modules can therefore be rapidly added to a system or withdrawn from a system in order to modify the latter.
Such a system is described in an article of Jan. 1.sup.st 1985 in the magazine "Electronics Week", pages 97,98, entitled "Domino-like Modules build Computers" and represented by the photograph accompanying this article. A system of the same kind is described in greater detail in U.S. Pat. No. 4,045,105. These systems are based on the use of pins and sleeves, which are complex and comparatively expensive; moreover, these pins introduce intermediate contacts between two adjacent circuits, which increases the resistance of the connections and decreases the reliability.